Improvement in the use of caseine for making printers  blocks



NI'IED STATES t .r on.

THOMAS J. DENNE, OF MILE END, LONDON, ASSIGNOR OF ONE-HALF OF HIS RIGHT TO AUGUST HENTSOHEL, OF ISLINGTON, ENGLAND.

IMPROVEMENT INTHE USE OF CASEINE FOR MAKING PRINTERS BLOCKS.

Specification forming part of Letters Patent No. 127,032, dated May 21, 1872.

To all whom it may concern:

Be it known that I, THOMAS JAMES DENNE, of Mile End, London, in the county of Middlesex, England, have invented or discovered certain new and useful Improvements in the lows: I take my caseine and dissolve it in wa-,

ter with a few drops of ammonia. To one part caseine I add about (an exact quantity is not material) four to six parts of either China-clay, pipe-clay, flake-white, or similar substance, and a small quantity of glycerine or salt to it; mix

' these together, and coat with this composition paper, card-board, wood, slate, metal, or any required material. I smooth the surface, and make it insoluble in water by brushing it over with a weak solution of acetic acid. When this surface or composition is set and dry it is what I call a plain block, and, presumably, the composition is on card-board. Now, by sensitizing such a plain block by the ordinary methods pursued by photographers, it can be printed upon, by the action of light in the usual photographic way, from negatives or positives;

. and, when so printed, I can, by the process of,

as it is termed, washing out, obtain a surface in intaglio or relief, as I desire; and it would be, according to the nature of the after process desired, a casting-block or printingblock from which other blocks can be made by the ordinary method well understood by mechanics in molding and casting trades, and by stereotypers and electrotypers; and the form or shape of such blocks or patterns can be according to the want and requirement of them, and are not bound to a particular and fixed form, nor to any particular metal to be cast in the molds formed from the castingblocks. I can also make from the plain block, when sensitized as after shown, by direct drawing upon it, a casting or printing block thus: I make an ink composed of bichromate of potassa, Indian ink, or lamp-black, and gum, and with this ink I draw upon the surface of a plain block a desired object, and when drawn expose it to the action of ordinary (day) light; this hardens the drawing, and when it is dry and hardened the parts of the composition of the block not drawn upon can be washed or brushed out with a solution of soap, soda, and water, leaving the drawing standing in relief. If it is desired to harden the drawing more than the above ink will do it, I add to the ink a metal oxide.

I now proceed to show how I copy a negative upon a plain block, (still presumably made on card-board,) and in so doing form a casting or printing block. I brush the plain block over with a saturated solution of bichromate of potassa, in a dark room, such as is used in ordinary photographic operations. This block, when sensitized, I expose, under a negative, to light, to print; and when it is printed to the required degree the unprinted portions of the block are washed and brushed out with soap and soda solution, leaving the picture standing in relief, from which a casting or printing block can be made.

I now proceed to show my method of making a paper negative for working on a plain block, by means of which I am enabled to reproduce and multiply fac-simile impressions of drawings, designs, or writings. I take my caseine in solution, and add to it Indian ink or lamp-black, and with this mixture I make a drawing, presumablyv on paper. After this I cover the whole surface of the paper with lithographic ink, (other printing-ink will also do,) and then put the paper in water, to which a few drops of .ammonia have been added, and the drawing, with its covering of ink, will wash away, leaving the undrawn parts black, through which light cannot penetrate, and the drawn part white. This paper being, as it is termed, photographically exposed to light upon a sensitized plain block, the light penetrates through the parts that have been drawn upon, prints that part of the sensitized plain block on which it can act, rendering it insoluble to the soap and soda solution, which dissolves those parts of the block lying under the black parts of the negative, through which the light cannot penetrate, and which, not being acted upon, remain soluble to the solution, and by the washing and brushing out this portion of the sensitized plain block is removed, leavin g the drawing standing in relief.

I now proceed to show my method of making a printing-block to print what is known as half-tone printing, whereby I am enabled to obtain a stereotype or eleetrotype plate directly from a negative, without employing a separate plain block. I here produce the printin g-block upon the surface of the negative itself. I take the composition with which I make the plain block, or a composition of three parts caseine and one part soap, boiled together, (the exact proportions are not material,) and to either or both of these compositions Imix sufficient bichromate of potassa in solution to make it the color Irequire. This composition is then, from the admixture of bichromate of potassa, sensitive to light. I then take a glass negative and coat it with this composition in a dark room, expose it to the light, and print the composition through the negative; and when it is sufficiently printed I wash and brush out those parts of the composition on which the light has not acted with the soap and soda solution, leaving the composition picture on the negative, and from this electrotypes or stereotypes can be taken in the usual manner.

It will be seen that in whatever manner my compositions, formed by the admixture of caseine and China-clay, pipe-clay, or flake-white, to which has been added glycerine or salt or caseine and boiled soap, as I have shown, spread upon another surface, (which, for clearness, I have confined to card-board,) and sensitized, that this sensitized composition can be printed, and will harden under the influence of light, and, where not so acted upon, can be, as it is termed photographically, washed out, leaving the drawing in relief or intaglio, as required; and it must be borne in mind that although I have all along in these descriptions dealt with my improved naturally-made caseine for the purpose of distinguishing it from the caseine which is well known in commerce, yet that the caseine of commerce, if used in the way I have shown, will also give like results, but inferior ones, and this arises from difference of the manufacture of the two caseines, although both are from the same base, (milk,) and this remark holds good throughout this specification whenever the substance caseine forms part of a composition to be em ployed in carrying out my invention.

I now proceed to show my method of photolithography, which is simply a method of transferring copies of photographic pictures onto a lithographic stone, and thus of obtaining a printing surface or block on stone to be printed from. I make a composition of three parts caseine and one part soap, boiled together, (the exact proportion is not material,) and add to this bichromate-of-potassa solution, allow it to cool, and then coat paper with this in a dark room. When the composition is dry upon the paper I expose it under a negative to the light to print. I then roll the print in with litho or other suitable ink, thus: Roll a stone up black, lay on it the picture, and pull it through the printing-press. This covers the whole surface of the picture with the ink. I then plunge the picture in water, to which has been added a few drops of ammonia. This dissolves out the parts that have not been acted upon by the li ght--as it is termed,washes them away-leavin g the picture still covered with ink upon the paper, and this is transferred down upon a lithographic stone in the ordinary manner, to be printed from it in the usual way. Either my improved naturally-made caseine or the caseine of commerce can be used for this purpose, as shown, but the latter gives inferior results.

I now proceed to show my method of making a printing-block on zinc by what is termed zinco-photography, thus: I make a composition as for photo-lithography, mixed with the bichromateof-potassa solution, and give with this a thin layer on zinc, and expose it under a negative to print. When printed I dissolve the unprinted portion .away with ammoniawater. I then wash the surface well with clean water and make the print insoluble with acetic acid, and it is then ready for etching in the usual and well-known manner.

I now proceed to show my process of making a printing-block on zine by what is termed zinco-graphotype, thus: I cover a zinc plate with a composition made of two parts caseine and one part soap, boiled together, (the exact proportion is not material,) to which is added Frankfort or other black, ground in glycerine and water. I draw upon the covered plate with a suitable point, so as to remove the coating, and brush the drawing over with asphalt dissolved in turpentine. When this is dry I plunge it in weak ammonia-water, which dissolves away all but the parts drawn, and from which the original coating has been removed. It is then washed in clear water and it is ready for etching in the usual and well-known manner. This process is also applicable to other meta-ls. Either my improved naturally-m ade caseine or the caseine of commerce can be used for the purpose of zinco-photography or zinco graphotypc, as shown, but the latter gives inferior results.

I nowproceed to show another method of preparing the surfaces of wood, metal, paper, or other substances, which is especially applicable to the preparation of a printing-block.

on wood, and which also gives valuable results in ordinary photographic printing. I take my improved naturally-made caseine, dissolve it, and add to it a sufficient quantity of zincwhite or white lead. To give substance and tone there must also be an admixture of a small quantity of chloride of ammonia, and coat the wood with this composition. The wood is, by preference, an ordinary boxwood block, such as is usual for wood engravers to work upon, and when this coating is dry I coat it again with nitrate of silver in solution, and then expose theblock under a nega tive or positive to print photographically in the ordinary way. When printed I fix the print with a solution of hyposulphite of soda, and it is then ready for the wood engraver to engrave it. I have said that I make this composition from my improved naturally-made caseine. I do this by preference, because it gives a finer picture with more sharpness and detail; but the caseine of commerce can be used, although it gives, in proportion to the other, very indifferent results.

In printing on wood I may modify the composition by substituting for the zinc-white or white lead such substances as China-clay, pipeclay, flake-white, &o.

If it be required to make a photograph-print in this manner upon paper, insoluble, I wash it with acetic acid. This photograph can be, if preferred, toned in the usual Way; but I think it is unnecessary, as the picture comes up so well otherwise. In making the composition for covering wood, metal, paper, or any required materials, no particular proportions of quantity can be given as fixed, because widely-different proportions will give pictures whose chief difference will be in their color.

Having now described and particularly ascertained the nature of my said invention, and the manner in which the same is. or may be used or carried into efi'ect, I observe, in conclusion, that what I consider to be novel and original, and therefore claim as my invention, 1s-

1. The preparation of the surfaces of cast ing and printing blocks to be formed in in taglio or relief, by means of a composition consisting of an admixture of caseine, China-clay, &c., prepared and treated as hereinbefore described, and which composition is also applicable for the preparation of a printing-block in intaglio or relief directly upon the negative, for half tone printing, as hereinbefore described.

2. The preparation of the surface for an artificial negative on paper by means of a composition formed of caseine and Indian ink or lamp-black, as hereinbefore described.

3. The preparation of the surface of paper by means of a composition containing caseine,

soap, and bichromate of potassa, whereby I am enabled to transfer any drawing, design, or writing to a lithographic stone for lithographic printing, as hereinbefore described, and which composition may also be applied in the preparation of the surface of zinc, as in the process of zinco photography hereinbefore described.

4. The preparation of the surface of zinc by means of a composition containing caseine, soap, and Frankfort or other black, to be used in the zinco-graphotype process, as hereinbefore described, and which composition may also be applied to other metals.

5. The preparation of surfaces on wood, pa per, 850., by means of a composition containing caseine, zinc-white or white lead, with a small addition of chloride of ammonia, or the modification thereof, as hereinbefore described.

In witness whereof, I, the said THOMAS JAMES DENNE, have hereunto set my hand this fifth day of January, one thousand eight hundred and seventy-two.

T. J. DENNE.

Witnesses:

DANL. FORSHAM,

Of 24 Royal Exchange, London. G. W. WESTLEY,

24 Royal Exchange, London. 

